Globular thiab fibrillar protein: yooj yim yam ntxwv

Cov plaub tseem ceeb tshaj plaws chav kawm ntawm organic tebchaw uas yog ib feem ntawm lub cev: nucleic acids, Sibhawm, carbohydrates thiab proteins. Nyob rau tom kawg yuav ua tau los sib tham nyob rau hauv no tsab xov xwm.

Yuav ua li cas yog protein?

Qhov no polymer tshuaj tebchaw ua los ntawm cov amino acids. Cov nqaijrog muaj ib tug complex qauv.

Raws li tsim protein?

Qhov no tshwm sim nyob rau hauv lub hlwb ntawm tus kab mob. Tshwj xeeb organelles uas yog lub luag hauj lwm rau tus txheej txheem no. Qhov no ribosome. Lawv muaj xws li ob qhov chaw: me me thiab cov loj loj, yog ua ke thaum lub sij hawm organelle. Tus txheej txheem ntawm synthesizing lub polypeptide chains ntawm amino acids yog hu ua neeg txhais lus.

Yuav ua li cas yog amino acids?

Txawm tias muaj tseeb hais tias cov ntau ntau yam ntawm cov nqaijrog nyob rau hauv lub cev countless, amino acids, los ntawm uas lawv muaj peev xwm yuav tsim nyob rau, muaj tsuas yog nees nkaum. Xws li ib tug ntau haiv neeg ntawm cov nqaijrog yog tiav los ntawm txawv ob peb ua ke thiab sequences ntawm amino acids, raws li ntau yam kev pab chaining nyob rau hauv qhov chaw.

Amino acids muaj nyob rau hauv lawv cov tshuaj nyob tus yeees ntawm ob tawm tsam thaj chaw ntawm functional pawg: carboxyl thiab amino pab pawg neeg, thiab cov radical: ntxhiab, aliphatic los yog heterocyclic. Ntxiv mus, ntxiv functional pawg yuav incorporated mus ua radicals. Cov no yuav carboxylic acid pab pawg, amino pawg, amide, hydroxyl, guanidovye pab pawg neeg. Tsis tas li ntawd, cov radical tau muaj leej faj nyob rau hauv lawv cov muaj pes tsawg leeg.

Ntawm no yog ib daim ntawv teev acids uas los ntawm cov nqaijrog yuav raug ua lub tsev:

• alanine;
• glycine;
• leucine;
• valine;
• isoleucine;
• threonine;
• serine;
• glutamic acid ;
• aspartic acid ;
• Glutamine;
• asparagine;
• arginine;
• lysine;
• methionine;
• cysteine;
• tyrosine;
• phenylalanine;
• histidine;
• tryptophan;
• proline.

Ntawm no, kaum yog qhov tseem ceeb - cov uas yuav tsis raug tsim nyob rau hauv tib neeg lub cev. Qhov no valine, leucine, isoleucine, threonine, methionine, phenylalanine, tryptophan, histidine, arginine. Lawv yuav tsum tau noj cov zaub mov. Muaj ntau ntawm cov amino acids pom nyob rau hauv cov ntses, nqaij nyuj, nqaij, ceev, legumes.

Lub hom qauv ntawm cov protein - yog dab tsi?

Qhov no ib theem zuj zus ntawm cov amino acids nyob rau hauv cov saw hlau. Paub txog thawj qauv ntawm cov protein, nws yuav ua tau ib tug caij nyoog tshuaj mis.

theem nrab qauv

Nws yog ib txoj kev sib ntswg ntawm lub polypeptide saw. Muaj ob qho kev xaiv rau cov configuration ntawm cov protein alpha-helix thiab beta-qauv. Cov theem nrab qauv ntawm cov protein yog muab los ntawm hydrogen bonds ntawm cov npog yaig thiab NH- pawg.

Lub tertiary qauv ntawm cov protein

Qhov no spatial orientation ntawm ib tug kauv los yog ib txoj kev tso ib tug tej yam twg. Nws muab disulfide thiab peptide tshuaj bonds.

Nyob ntawm seb lub hom tertiary lug nyob fibrous thiab globular proteins. Cov yav tas muaj ib tug kheej kheej zoo. Qauv fibrillar cov nqaijrog tsa xov uas yog tsim los ntawm lub multilayer stacking beta lug los yog thaum uas tig mus uake ntawm ob peb alpha-lug.

Lub quaternary qauv

Nws yog cov yam ntxwv rau cov nqaijrog uas tseem muaj li ntawm tsis yog ib, tab sis ob peb polypeptide chains. Tej proteins uas hu ua oligomeric. Cov chains muaj nyob rau hauv lawv cov muaj pes tsawg leeg, hu ua protomers. Protomers, uas yog tsim los ntawm ib tug oligomeric protein yuav muaj ob lub yam los yog txawv rau cov thawj, theem nrab los yog tertiary qauv.

Yuav ua li cas yog denaturation?

Qhov no kev puas tsuaj rau lub quaternary, tertiary, theem nrab protein lug, uas nws loses nws tshuaj thiab lub zog thiab muaj peev xwm tsis txaus siab rau nws cov luag hauj lwm nyob rau hauv lub cev. Qhov no txoj kev muaj peev xwm tshwm sim raws li ib tug tshwm sim ntawm kev kub muaj peevxwm protein (los ntawm 38 degrees Celsius, tab sis rau txhua tus neeg protein, qhov no daim duab) los yog txhoj puab heev tshuaj xws li acids thiab alkalis.

Ib txhia cov nqaijrog muaj peev xwm ntawm annealing - lub resumption ntawm nws cov thawj qauv.

kev faib ntawm cov nqaijrog

Muab cov tshuaj nyob tus yeees, lawv muab faib ua tej yam yooj yim thiab complex.

Tej yam yooj yim cov nqaijrog (cov nqaijrog) - yog cov neeg uas muaj tsuas cov amino acids.

Complex cov nqaijrog (proteid) - cov neeg uas muaj li ntawm ib tug prosthetic pab pawg neeg.

Nyob ntawm seb lub hom prosthetic pab pawg neeg ntawm cov nqaijrog yuav tau muab faib mus rau hauv:

• lipoprotein (muaj lipids);
• nucleoproteins (muaj muaj nucleic acids);
• chromoproteids (muaj pigments);
• fosfoproteidy (yog muaj li ntawm phosphoric acid);
• metalloproteins (muaj co);
• glycoproteins (muaj noj carbohydrates).

Tsis tas li ntawd, nyob ntawm seb lub hom globular tertiary qauv tshwm sim thiab fibrillary protein. Ob leeg yuav ua tau raws li tej yam yooj yim los yog txoj.

Thaj chaw ntawm fibrous cov nqaijrog thiab lawv lub luag hauj lwm nyob rau hauv lub cev

Lawv yuav tsum tau muab faib ua peb pawg nyob rau hauv lub thib ob qauv:

• Alpha-qauv. Cov no muaj xws keratin, myosin, tropomyosin thiab lwm tus neeg.
• Beta qauv. Piv txwv li, fibroin.
• Collagen. Qhov no protein, uas muaj ib tug tshwj xeeb theem nrab qauv, uas yog tej nuj nqis alpha-helix los yog cov beta-qauv.

Properties fibrillar cov nqaijrog nyob rau hauv tag nrho peb pawg lus dag nyob rau hauv lub fact tias lawv muaj ib tug filamentary tertiary qauv, thiab yog tsis soluble nyob rau hauv cov dej.

Cia tus tham txog lub ntsiab fibrillar cov nqaijrog ntau nyob rau hauv kev txiav txim:

• Keratins. Qhov no tag nrho cov pab pawg neeg ntawm ntau haiv neeg cov nqaijrog, uas yog lub ntsiab tivthaiv ntawm cov plaub hau, ntsia thawv, plaub, ntaub plaub, horn, hooves thiab cov zoo li. D. Tsis tas li ntawd, lub fibrillar protein cytokeratin no pab pawg neeg yog ib feem ntawm lub hlwb txoj kev cytoskeleton.
• Myosin. Qhov no tshuaj, uas yog ib feem ntawm cov nqaij fibers. Nrog rau actin, lub fibrillar protein yog ib tug contractile thiab kom cov hauj lwm rau cov nqaij ntshiv.
• Tropomyosin. Qhov no cov ntaub ntawv uas muaj ob intertwined alpha helices. Nws kuj yog ib feem ntawm cov nqaij.
• Fibroin. Qhov no protein yog tso tawm los ntawm ntau yam kab thiab arachnids. Nws yog lub ntsiab tivthaiv ntawm lub web thiab txhob lo lo ntxhuav.
• Collagen. Qhov no yog feem ntau fibrillar protein nyob rau hauv tib neeg lub cev. Nws yog ib feem ntawm lub txog leeg, pob txha mos, nqaij, cov hlab ntsha, daim tawv nqaij, thiab hais txog. D. Qhov no cov ntaub ntawv uas muab elasticity ntaub so ntswg. collagen nyob rau hauv lub cev txo nrog lub hnub nyoog, thiab yog li ntawd lub wrinkles tshwm sim ntawm daim tawv nqaij, weaker ligaments thiab tendons, thiab t. d.

Tom ntej no xav txog lub thib ob pab pawg neeg ntawm proteins.

Globular cov nqaijrog: ntau ntau yam, lub zog thiab roj ntsha luag hauj lwm

Tshuaj ntawm no pab pawg neeg muaj ib tug kheej kheej zoo. Lawv yuav ua tau soluble nyob rau hauv dej, alkali kev daws teeb meem, acids thiab ntsev.

Cov feem ntau globular cov nqaijrog nyob rau hauv lub cev yog:

• Albumins: ovalbumin, lactalbumin, thiab lwm yam ..
• Globulins: ntshav cov nqaijrog (e.g., hemoglobin, myoglobin.) Thiab lwm tus neeg.

Xav paub ntau ntxiv txog lawv tej:

• Ovalbumin. Qhov no protein muaj xws li 60 feem pua qe dawb.
• Lactalbumin. Lub ntsiab tivthaiv ntawm cov mis nyuj.
• Hemoglobin. Qhov no txoj globular protein, uas muaj raws li cov heme prosthetic pab pawg neeg yog tam sim no - yog ib tug pab pawg neeg ntawm cov xim muaj hlau. Hemoglobin yog muaj nyob rau hauv cov ntshav liab. Qhov no protein, uas muaj peev xwm sawv ntawm losis tswvyim dabtsi nrog cov pa thiab thauj nws.
• Myoglobin. Nws yog ib tug protein zoo xws li cov hemoglobin. Nws ua ib tug yam ntxwv - mus nqa oxygen. Xws li ib tug protein muaj nyob rau hauv cov nqaij (mob thiab striated).

Tam sim no uas koj paub qhov yooj yim sib txawv ntawm tej yam yooj yim thiab complex, fibrillar thiab globular proteins.